Haversian canals are narrow tubes within compact bone containing blood vessels and nerves. They generally run parallel to the bone surface. Each canal surrounded by a series of rings of bone (lamellae) is known as a Haversian system. Main function of Haversian system is transportation of nutrients and O 2 through blood. Haversian canals are connected by horizontal Volkmann-?s canals. They provide the major route for blood vessels from the marrow cavity to the Haversian canals of osteons.